Slipring unit

ABSTRACT

An electrical slipring having a nonconductive support with a plurality of circular recesses and bores open to the bottom of each recess. A flat annular electrical conductive member is located in each recess. Each member has a boss located in a bore in the support. Fasteners projected through the support secure the annular members to the support.

United States Patent Inventor Floyd E. Buschbom Long Lake, Minn. Appl. No. 793,212 Filed Oct. 23, 1968 Division of Ser. No. 501,159, Oct. 22, 1965, Pat. No. 3,438,123 Patented July 20, 1971 Assignee VanDale Corporation Wayzata, Minn.

SLIPRING UNIT 10 Claims, 7 Drawing Figs.

us. CL 339/8, 339/217 Int. Cl. H01r 39/34 Field of Search 339/5, 8, r 270,2l7,214,232

References Cited UNITED STATES PATENTS Carlson Seim...........

Girton Norden Olson Rutten.... Schaefer Primary Examiner-Richard E. Moore Attorney-Burd, Braddock & Bartz BS RACT: An electrical slipring having a nonconductive support with a plurality of circular recesses and bores open to the bottom of each recess. A flat annular electrical conductive member is located in each recess. Each member has a boss located in a bore in the support. Fasteners projected through the support secure the annular members to the support.

SLIPRING UNIT CROSS-REFERENCE TO RELATED APPLICATION This application is a division of application Ser. No. 501,159, filed Oct. 22, 1965, now US. Pat. No. 3,438,123 issued Apr. 15, 1969 for Method of Making a Slip Ring Unit.

This invention relates to an electrical connection. More particularly, the invention is directed to an electric contact ring assembly having a slipring unit cooperating with a brush unit to make an electrical connection.

As disclosed in US. Pat. Nos. 2,794,560 and 3,l8l,7l5 a group of top-traversing silo unloaders have electric contact ring assemblies or transition assemblies for transferring current from a stationary portion of the machine to a portion of the machine rotatable about a vertical axis for collecting silage and delivering silage to the stationary portion. These contact ring assemblies have slipring units which are expensive to manufacture as they require many separate fabricating operations as well as waste a considerable amount of conductive material, as copper. When the annular metal conductive rings and the nonconductive ring support of the slipring unit are combined by molding the support about the rings the unequal coefficients of thermoexpansion and contraction of the metal rings and the synthetic resinous support cause the rings to warp on cooling as well as separate portions of the rings from the support. Portions of the support are placed under stress making the support susceptible to breakage in use.

It is the object of this invention to provide an improved electric ring contact assembly for a silo unloader which has economy in construction, minimizes labor and waste material in fabrication and is sturdy andreliable in use.

Another object of the invention is to provide a slipring unit having a plurality of annular conductor rings which can be assembled and disassembled in a minimum of time and labor on a support of nonconductive material.

IN THE DRAWING:

FIG. I is a sectional view of the electric contact ring assembly of this invention on a silo unloader;

FIG. 2 is an enlarged sectional of a fragmentary portion of the conductor slipring unit of the electric contact ring assembly of FIG. 1;

FIG. 3 is an enlarged sectional view of another fragmentary portion of the conductor slipring unit of the electric contact ring assembly of FIG. 1;

FIG. 4 is a fragmentary perspective view of the metal conductor ring casting;

FIG. 5 is a plan view of the bottom of the metal conductor ring casting;

FIG. 6 is a plan view of the conductor slipring support; and

FIG. 7 is an enlarged sectional view taken along the line 7-7 of FIG. 6.

Referring to the drawing, there is shown in FIG. 1, the electrical contact ring assembly or transition assembly of this invention indicated generally at 10 for a silo unloader such as the silo unloader in US. Pat. No. 2,794,560. The electrical contact ring assembly 10 comprises a stationary subassembly 7 11 positioned above a rotatable subassembly 1-2 connected to the stationary subassembly 11 for rotation about a generally upright axis. subassembly 11 comprises an upright tubular member I3 having an upright Venturi-shaped passage 14 for directing material into a chute l6 projected upwardly and outwardly toward the silo wall. Chute I6 is pivotally mounted to the top of the tubular member 13 by a pair of bolt and nut assemblies 17 one of which is shown. Integral with the midportion of the tubular member [3 is an annular outward radial flange 18 having a downwardly projected peripheral sidewall 19. A heave annular member or ring 21 is secured to the lower end of the sidewall 19. Radial flange I8 and sidewall 19 define an annular chamber 22 accommodating a slipring unit indicated generally at 23. Bolts 24 projected through suitable holes in circumferentially spaced ears 25 integral with the 75 periphery of support 23 and threaded into bores in the flange I8 secure the slipring unit 23 to the flange 18. When the slipring unit 23 is mounted on flange 18 a portion of the slipring unit projects through opening 26 into an enclosed junction box defined by an upright wall 27 on flange 18. The top of the upright wall 27 has an opening 28 covered by a flat closure 29.

Subassembly 12 has an upright tubular member 31 adapted to be secured to the discharge structure of a silo unloader impeller housing to receive material into upright passage 32 and direct the material to the upright passage 14 of the stationary subassembly ll. Tubular member 31 has an integral radial flange 33 having a circumferential end section riding on the top of annular ring 21. The lower end of tubular member 13 has a downwardly projected annular lip 34 extended into an annular recess in the top of the tubular member 31. An annular seal 36 interposed between the top of the flange 33 and the tubular member 13 prevents entrance of foreign material into the annular chamber 22. Grease fittings 37 are used to lubricate engaging surfaces of the subassemblies I1 and 12.

Flange 33 has an opening 38 accommodating a brush unit indicated generally at 39. Included in the brush unit 39 is a support 41 of nonconductive resinous material having upright bores for accommodating six spaced brushes 42 having flat upper ends in engagement with the slipring unit 23. Springs 43 engage each of the brushes 42 and bias them in an upward direction. Projected downwardly from each brush 42 are conductor elements terminating in eyes 45 adapted to be connected to lines leading to an electric motor or the like, used to operate the silo unloader.

Slipring unit 23 has three metal annular conductors or sliprings 44, 46 and 47. Each of the conductors are flat annular cast metal members cast from conductive metal material such as copper, copper alloys and the like Sliprings 44, 46 and 47 are identical except for the difference in the diameters of the rings. Rings 44, 46 and 47 are mounted in concentric and spaced relative relation in an annular support 48 of nonconductive material such as a hard synthetic resinous material. Support 48 has three annular and concentric recesses or channels 49, 51 and 52 defined by concentric annular walls 53 and 54 and inner and outer annular walls 55 and 56 concentric with the walls 53 and 54.

Referring to FIG. 3, there is shown an enlarged portion of support 48 in assembled relation with the sliprings 44, 46 and 47. The base of each of the recesses 49, 51 and 52 has an annular groove 57 receiving a rectangular lug 58 integral with the top side of the slip ring 46. The lug 58 has a threaded bore 59 receiving a screw 60 projected through a suitable hole in the flat base of the support 48. The head of the screw 60 is located in a recess 61 and covered with a nonconductive material 62.

As shown in FIG. 4, each slipring 44, 46 and 47 has two circumferentially spaced rectangular lugs 58A and 58B identical with the lug 58 for receiving screws to secure the rings to support 48. Circumferentially spaced between each of the lugs 58, 58A and 58B on each ring are upwardlyprojected tapered bosses 63, 63A and 638. As shown in FIG. 2, boss 63 is cast integral with slipring 46 and tapers inwardly in an upward direction. Boss 63 projects through a tapered opening 64 in a collar 65 integral with the base 48. A threaded bore 66 extends axially into boss 63 and accommodates a bolt 67 used to secure electrical conductor 68 to the boss 63. The top of the boss 63 is flush with the top collar 65. A copper washer is secured to the top of boss 63 with bolt 67. The lower side of slipring 46 has a flat smooth and continuous face 69 engageable with the flat end of the middle two brushes 42 to provide an electrical contact between slipring 46 and middle two brushes 42 whereby electric power may be transmitted through the conductor 68, the slipring 46, the middle two brushes 42, and to the electric motor driving the silo unloader. Rings 44 and 47 are positioned in recesses 49 and 52 and secured to support 48 in the same manner as ring 46. Bosses 63A and 638 project through collars 65A and 65B respectively on support 48.

In the method of fabrication of the ring unit 23 the annular sliprings 44, 46 and 47 are initially cast of electrically conductive metal in three concentric spaced rings as shown in FIG. 4 and indicated generally by single casting 71. Casing 71 is made in a single casting operation of electrically conductive metal, such as copper, copper alloys and the like. The rings are substantially flat annular members connected with a plurality of circumferentially spaced flat runners or gates 72 and 73. The tapered boss 673 is integral with and projects upwardly from the top of the ring 46. In the same manner tapered bosses 63A and 638 project upwardly from the annular sliprings 44 and 47, respectively. Circumferentially spaced from the bosses 63, 63A and 63B are upwardly projected lugs 58, 58A and 588.

The lugs are rectangular shaped and have a width narrower than the width of the associated slipring. As shown in FIG. 5, each slipring has a flat continuous face 69, 69A and 698 on the side opposite the bosses and lugs. Rings 44, 46 and 47 as a single casting are pressed flat with rollers into a single plane. The faces 69, 69A and 69B are machined into smooth continuous surfaces. The machining of the slipring is completed by providing bosses 63, 63A and 638 as well as lugs 58, 58A and 588 with threaded axial bores 66 and 59, respectively. After the machining operations are completed the rings 44, 46 and 47 are separated from each other by removing all the gates 72 and 73.

Referring to FIGS. 6 and 7, the support 48 is a one-piece annular member molded from synthetic resinous nonelectrical conductive material. The lower side of the support 48 has three concentric recesses or grooves 49, 51 and 52 separated by concentrically disposed circular walls 53, 54, 55 and 56. The tapered bores of each of the cylindrical projections or collars 65, 65A and 658 open to the base of the grooves. The inside collar 65A is longer than collars 65 and65B. As shown in FIG. 6, collar 65 is circumferentially spaced from collars 65A and 65B. Circumferentially spaced from collars 65, 65A and 65B and open to the grooves are holes 74 for accommodating the screws 60 used to secure the sliprings to support 48.

The sliprings 44, 46 and 47 are assembled on support 48 by placing the slipring 44 in the groove 49 with the tapered boss 63A projected through the cylindrical projection 65A. This aligns holes 74 with threaded bores in the rectangular lugs 58A. Screws similar to screw 60 are used to secure the ring 44 to the support 48. The heads of the screws are located in recesses which are filled with a nonconductive material. In a similar manner rings 46 and 47 are mounted in the support 48 and secured thereto with screws 60. The machined smooth flat surfaces 69, 69A and 69B of each of the conductor rings are located along the base sections of the grooves 49, 51 and 52 providing three concentrically spaced continuous electrical conductors.

As shown in FIG. 1, the ring unit 23 is positioned in the annular chamber 22 and secured to the stationary flange 18 by bolts 24 projected through the holes in the support ears 25. With the ring 21 removed the stationary subassembly 25 is then placed over the flange 33 of the movable subassembly 12. Ring 21 is then secured to the end of the sidewall 19 to couple the stationary subassembly 11 to the rotatable subassembly l2. Brush unit 39 is then inserted through the opening 38 in the flange 33 with the brushes 42 projected into the annular recesses 49, 51 and 52 engaging the flat continuous surfaces of the sliprings 44, 46 and 47, respectively.

In use, electricity is transmitted from any suitable source of electric current by a powerline or cable into the junction box 27 and by leads to the terminals 67, 67A and 678 on the upper ends of bosses 63, 63A-and 63B. Electric current is then transferred through the bosses to the annular sliprings 44, 46 and 47. Brushes 42 maintained in communication with the sliprings by the springs 43 pick up the electric current which is transferred via a cable to an electric motor mounted on the rotating part of the silo unloader. As subassembly l2 of the silo unloader rotates it moves brushes 42 around the sliprings 44, 46, and 47 which are held stationary with the subassembly 11. The silo unloader will convey and move ensilage upwardly through the passages 32 and 14 and outwardly through the chute 16 as shown by arrows in FIG. I. I

The specific embodiment described is given by way of example. The invention is limited only by the terms of the appended claims.

The embodiments of the invention in which I claim an exelusive property and privilege are defined as follows:

1. A slipring unit comprising a support of electrically nonconductive material, said support having a circular recess and a groove in the bottom of the recess, at least one bore open to the bottom of the recess, a flat annular member of electrically conductive material having a width and diameter substantially the same as the width and diameter of the recess and a thickness substantially less than the depth of the recess enabling the annular member to fit into the circular recess over the bottom of the recess, the outer face of the annular member being smooth and continuous, a boss attached to the annular member and projected through said bore, said boss having a size and shape substantially the size and shape of the bore, lug means attached to the annular member, said lug means projected into the groove, and fastening means pro jected through said support and attachable to said annular member for securing the annular member to said support.

2. The slipring unit defined in claim 1 wherein said lug means has means coacting with said fastening means for securing the annular member to the support.

3. The slipring unit defined in claim I further characterized by a collar projected from the support forming an extension of the bore, said bore having an outwardly tapered shape and being open to the bottom of the recess said boss having a tapered shape to fit into said bore.

4. The slipring unit defined in claim 1 wherein said annular member and boss are a single cast metal member.

5. A slipring unit comprising an annular support of electrically nonconductive material having a side formed with a plurality of concentric circular recesses and a groove in the bottom of each recess, said support having at least one transverse bore open to the bottom of each recess, sliprings of electrically conductive material positioned along the bottom of said concentric circular recesses, each of said sliprings having a flat. smooth and continuous outer face, lug means projected into the groove, and a boss projected through the bore open to the recess in which the slipring is positioned, said boss having a size and shape substantially the size and shape of the bore, and fastening means projected through said support and attachable to said sliprings for securing the sliprings to said support.

I 6. The slipring unit defined in claim 5 wherein said lug means has means coacting with the fastening means for securing the rings to the support.

7. The slipring unit defined in claim 5 further characterized by a plurality of collars projected from said support forming extensions of the transverse bores, each of said bores having an outwardly tapered shape, each of said bosses having a length and tapered shape to fit the bores.

8. The slipring unit defined in claim 5 wherein said sliprings are cast metal members.

9. The slipring unit defined in claim 5 wherein the groove in the bottom of each recess is an annular groove having a width less than the width of each said recess.

10. A slipring unit comprising a support of electrically nonconductive material, said support having a circular recess on one side thereof and a collar projected outwardly from the opposite side thereof, at least one bore extended through the collar and open to the bottom of the recess, a flat annular member of electrically conductive material located in said recess, said member having a width and diameter substantially the same as the width and diameter of the recess and a thickness substantially less than the depth of the recess whereby the annular member fits in the circular recess over the bottom of the recess, the outer face of the annular member being smooth and continuous, a boss attached to the annular member, said boss having a size and length substantially the same as the size and length of the bore and fastening means projected through said support and attachable to said annular member for holding the annular member in the recess and securing the annular member to the support.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 594 680 D t d y 20 1971 Floyd E. Buschbom Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 71, "heave" should be --heavy--.

Column 2, line 64, after "top" --ofis omitted.

Column 3, line 4, "casing" should be -casting-.

Column 3, line 9, "673" should be 63-.

Signed and sealed this 14th day of March 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents USCOMM-DC 60375-P69 FORM PO-1050 H0-691 v us. eovzmmsm PRINTING OFFICE I969 0-366-334 

1. A slipring unit comprising a support of electrically nonconductive material, said support having a circular recess and a groove in the bottom of the recess, at least one bore open to the bottom of the recess, a flat annular member of electrically conductive material having a width and diameter substantially the same as the width and diameter of the recess and a thickness substantially less than the depth of the recess enabling the annular member to fit into the circular recess over the bottom of the recess, the outer face of the annular member being smooth and continuous, a boss attached to the annular member and projected through said bore, said boss having a size and shape substantially the size and shape of the bore, lug means attached to the annular member, said lug means projected into the groove, and fastening means projected through said support and attachable to said annular member for securing the annular member to said support.
 2. The slipring unit defined in claim 1 wherein said lug means has means coacting with said fastening means for securing the annular member to the support.
 3. The slipring unit defined in claim 1 further characterized by a collar projected from the support forming an extension of the bore, said bore having an outwardly tapered shape and being open to the bottom of the recess said boss having a tapered shape to fit into said bore.
 4. The slipring unit defined in claim 1 wherein said annular member and boss are a single cast metal member.
 5. A slipring unit comprising an annular support of electrically nonconductive material having a side formed with a plurality of concentric circular recesses and a groove in the bottom of each recess, said support having at least one transverse bore open to the bottom of each recess, sliprings of electrically conductive material positioned along the bottom of said concentric circular recesses, each of said sliprings having a flat, smooth and continuous outer face, lug means projected into the groove, and a boss projected through the bore opEn to the recess in which the slipring is positioned, said boss having a size and shape substantially the size and shape of the bore, and fastening means projected through said support and attachable to said sliprings for securing the sliprings to said support.
 6. The slipring unit defined in claim 5 wherein said lug means has means coacting with the fastening means for securing the rings to the support.
 7. The slipring unit defined in claim 5 further characterized by a plurality of collars projected from said support forming extensions of the transverse bores, each of said bores having an outwardly tapered shape, each of said bosses having a length and tapered shape to fit the bores.
 8. The slipring unit defined in claim 5 wherein said sliprings are cast metal members.
 9. The slipring unit defined in claim 5 wherein the groove in the bottom of each recess is an annular groove having a width less than the width of each said recess.
 10. A slipring unit comprising a support of electrically nonconductive material, said support having a circular recess on one side thereof and a collar projected outwardly from the opposite side thereof, at least one bore extended through the collar and open to the bottom of the recess, a flat annular member of electrically conductive material located in said recess, said member having a width and diameter substantially the same as the width and diameter of the recess and a thickness substantially less than the depth of the recess whereby the annular member fits in the circular recess over the bottom of the recess, the outer face of the annular member being smooth and continuous, a boss attached to the annular member, said boss having a size and length substantially the same as the size and length of the bore and fastening means projected through said support and attachable to said annular member for holding the annular member in the recess and securing the annular member to the support. 